Tool

class Tool

Properties

name

the tool name the client calls

public readonly string $name

Type: string

inputSchema

JSON Schema describing the accepted arguments

public readonly array $inputSchema

Type: array

handler

the callable that executes the tool

private readonly \Closure $handler

Type: Closure

signature

reflection over the handler, used to bind named arguments

private readonly \ReflectionFunctionAbstract $signature

Type: ReflectionFunctionAbstract

description

what the tool does

public readonly string $description

Type: string

title

human-readable name for display

public readonly string $title

Type: string

annotations

behavioural hints for clients

public readonly array $annotations

Type: array

outputSchema

JSON Schema describing the structured result

public readonly array $outputSchema

Type: array

Methods

__construct

public __construct(string $name, array $inputSchema, \Closure $handler, \ReflectionFunctionAbstract $signature, string $description, string $title, array $annotations, array $outputSchema): void

Parameters

Parameter	Type	Description
$name	string	the tool name the client calls
$inputSchema	array	JSON Schema describing the accepted arguments
$handler	Closure	the callable that executes the tool
$signature	ReflectionFunctionAbstract	reflection over the handler, used to bind named arguments
$description	string	what the tool does
$title	string	human-readable name for display
$annotations	array	behavioural hints for clients
$outputSchema	array	JSON Schema describing the structured result

fromMethod

Builds a tool from an attributed controller method.

public fromMethod(object $controller, \ReflectionMethod $method, ToolAttribute $attribute): self

Returns: self

Parameters

Parameter	Type	Description
$controller	object	the server instance the method is called on
$method	ReflectionMethod	the attributed method
$attribute	Hazaar\MCP\Attribute\Tool	the attribute instance carrying the tool metadata

fromCallable

Builds a tool from an arbitrary callable registered at runtime.

public fromCallable(string $name, callable $handler, ?array $inputSchema, ?string $description): self

Returns: self

The schema is optional: when omitted it is derived from the callable's signature, exactly as it would be for an attributed method.

Parameters

Parameter	Type	Description
$name	string	the tool name
$handler	callable	the callable to execute
$inputSchema	array	JSON Schema for the arguments, or null to derive it
$description	string	what the tool does

toArray

Returns the tool definition as published by tools/list.

public toArray(): array

Returns: array

invoke

Binds the supplied arguments to the handler's signature and executes it.

public invoke(array $arguments): mixed

Returns: mixed

Parameters

Parameter	Type	Description
$arguments	array	the named arguments from tools/call

coerce

Converts a JSON-decoded argument into the type the parameter declares.

private coerce(\ReflectionParameter $parameter, mixed $value): mixed

Returns: mixed

JSON's type system is narrower than PHP's, and models are inconsistent about quoting numbers, so numeric strings are accepted where a number is wanted. Anything genuinely mismatched is rejected rather than silently coerced, since a wrong-typed argument that reaches the tool body produces a far more confusing failure.

Parameters

Parameter	Type	Description
$parameter	ReflectionParameter
$value	mixed

coerceEnum

Resolves a scalar argument to a backed enum case.

private coerceEnum(string $class, string $name, mixed $value): mixed

Returns: mixed

Parameters

Parameter	Type	Description
$class	string
$name	string
$value	mixed

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Generated by Hazaar API Doc Generator on Sun, 23 Aug 2026 10:49:44 +0000